Electric Power Management
The vehicle has Electric Power Management (EPM) thatestimates the battery's temperature and state of charge.It then adjusts the voltage for best performance andextended life of the battery.
When the battery's state of charge is low, the voltage israised slightly to quickly bring the charge back up.When the state of charge is high, the voltage is loweredslightly to prevent overcharging. If the vehicle has avoltmeter gage or a voltage display on the DriverInformation Center (DIC), you may see the voltagemove up or down. This is normal. If there is a problem,an alert will be displayed.
The battery can be discharged at idle if the electricalloads are very high. This is true for all vehicles. This isbecause the generator (alternator) may not be spinningfast enough at idle to produce all the power that isneeded for very high electrical loads.
A high electrical load occurs when several of thefollowing are on, such as: headlamps, high beams, foglamps, rear window defogger, climate control fan at highspeed, heated seats, engine cooling fans, trailer loads,and loads plugged into accessory power outlets.
EPM works to prevent excessive discharge of thebattery. It does this by balancing the generator's outputand the vehicle's electrical needs. It can increaseengine idle speed to generate more power, wheneverneeded. It can temporarily reduce the power demandsof some accessories.
Normally, these actions occur in steps or levels, withoutbeing noticeable. In rare cases at the highest levels ofcorrective action, this action may be noticeable to thedriver. If so, a Driver Information Center (DIC) messagemight be displayed, such as BATTERY SAVERACTIVE, BATTERY VOLTAGE LOW, or LOWBATTERY. If this message is displayed, it isrecommended that the driver reduce the electrical loadsas much as possible. SeeDIC Warnings and Messageson page 4!48.
Battery Run-Down Protection
This feature shuts off the dome lamps if they areleft on for more than 10 minutes when the ignition is inLOCK/OFF. This helps to prevent the battery fromrunning down.
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